Manager Lou Piniella of the Cincinnati Reds wrestled with relief pitcher Rob Dibble in the clubhouse at Riverfront Stadium Thursday night after a 3-2 victory over the Atlanta Braves that only slowed the Braves' NL West title drive.

The Reds trail the Braves by 9 1/2 games in the National League West and Atlanta's magic number for clinching is eight. About a half-hour after Steve Foster got his first major-league save, Dibble plunged the Reds into another controversy.

Piniella said he used Foster, who got the last three outs, because Dibble complained of a tight shoulder the previous night.

"Dibble was not available," Piniella said. "He couldn't get loose when he got up last night."

When reporters questioned the reliever about his shoulder, he shot back: "There's nothing wrong with it."

Piniella heard of Dibble's denial through reporters, then left his office and charged the pitcher in the clubhouse. Several players separated them as Piniella called Dibble a liar.

When reporters were allowed to return to the clubhouse, Piniella had nothing more to say.

"You all saw it," Piniella said. "Write it."

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If the Montreal Expos and Pittsburgh Pirates are tied for first place after 162 games, a one-game playoff will be held in Montreal, the National League office said.

Montreal General Manager Dan Duquette correctly called heads on a coin toss held in the office of NL President Bill White.

A playoff game would be played on Monday, Oct. 5.

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The baseballs used in next month's World Series will have more room for autographs because, for the first time in recent years, they will not bear the commissioner's signature.

Fay Vincent's resignation last week left Rawlings, which makes the balls, up in the air. On Wednesday, the manufacturer got the word.

"Major league baseball has requested that any World Series balls we stamp from now on have no signature," Rawlings spokesman Scott Smith said.

Instead, Smith said, the balls will read: Official Ball--1992 World Series.

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New York Met right fielder Bobby Bonilla had arthroscopic surgery on his right shoulder. . . . Atlanta Brave reliever Jeff Reardon said his strained hamstring has improved and should not prevent him from pitching.

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David H. Jacobs, 71, a prominent developer and co-owner of the Cleveland Indians, died at a hospital in Westlake, Ohio. A nursing supervisor said the cause of death was pneumonia.